I have had a few issues with Lightroom Mobile.

Lightroom Mobile on the iPhone had a major upgrade recently, but the iPad version did not.

Now it has.

Check out all the features in Lightroom Mobile for iOS 2.8 here. Below is an extract from that very web page.

"This release of Lightroom for mobile iOS rolls out the following new features and improvements for iPhone and iPad.

iPhone

New Brush Selection tool to selectively apply Exposure, Brightness, Clarity, and other adjustments to a specific part of a photo. Apple Pencil support for pressure-sensitive application of enhancements. 3D Touch support for pressure-sensitive application of enhancements on devices that support 3D Touch.

New Show Highlight Clipping feature in the in-app camera that shows you the over-exposed areas prior to capture.

New Brush Selection tool to selectively apply Exposure, Brightness, Clarity, and other adjustments to a specific part of a photo. Apple Pencil support for pressure-sensitive application of enhancements.